#include <iostream>
#include <cmath>
#include <algorithm>
#include <cstring>
#include <vector>
#include <map>
#include <queue>
#include <cstdio>
#include <string>
#include <stack>
#include <set>
#define IOS ios::sync_with_stdio(false), cin.tie(0)
using namespace std;
typedef long long ll;
ll num[110];
int main()
{
    IOS;
    ll ans=0;
    for(ll i=1;i<=100;i++){
        num[i]=num[i-1]+i;
        ans+=num[i];
    }
    cout<<ans<<endl;
    getchar();
    getchar();
    return 0;
}
